[Bug target/71767] Endless stream of warnings when using GCC with -Wa,-q and Clang Integrated Assembler

["iains at gcc dot gnu.org" <gcc-bugzilla at gcc dot gnu dot org>]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=71767

--- Comment #7 from Iain Sandoe <iains at gcc dot gnu.org> ---
(In reply to Dominique d'Humieres from comment #4)
> I see the problem after having updated to Xcode 8.0. I am currently testing
> the following patch

>  /* The .text section is generated in varasm.c  */
>  DEF_SECTION (text_coal_section, SECTION_CODE|SECTION_NO_ANCHOR,
> -	     ".section __TEXT,__textcoal_nt,coalesced,pure_instructions", 0)
> +	     ".section __TEXT,__text,coalesced,pure_instructions", 0)

actually, we need to come up with a patch that simply emits the text/etc.
section whenever it would have emitted the text_coal/etc. one.. So rather than
adjusting section definitions - we need to change which ones are selected in
config/darwin.c

.. but this should be conditional on a new enough linker to support it, or we
will break support for folks on ancient systems.  Is this repeatable without
xcode8?

I have some patches in progress to detect the linker features at configuration
time, so that we don't need to rely on guessing from the host system version. 
If this is not detectable by a linker feature, them perhaps we can determine
the earliest linker that can manage without the separate sections (most likely
considerably older than the one from Xcode8).